Answer:
[tex]\eta_{turbine} = 0.777 = 77.7\%[/tex]
[tex]\eta_{combined} = 0.728 = 72.8\%[/tex]
Explanation:
First we calculate the power input to the turbine. The input power will be equal to the potential energy of water per unit time:
Input Power = [tex]P_{in} = \frac{Work}{Time} = \frac{Potential\ Energy\ of\ Water}{t} \\P_{in} = \frac{(mass)(g)(height)}{Time} = (mass flow rate)(g)(height)\\\\P_{in} = (1500\ kg/s)(9.81\ m/s^2)(70\ m)\\P_{in} = 1.03\ x\ 10^6\ W = 1030\ KW[/tex]
Now, for turbine efficiency:
[tex]\eta_{turbine} = \frac{Mechanical\ Power\ Out}{P_{in}}\\\\\eta_{turbine} = \frac{800\ KW}{1030\ KW}\\\\\eta_{turbine} = 0.777 = 77.7\%[/tex]
for generator efficiency:
[tex]\eta_{generator} = \frac{Power\ Generation}{Mechanical\ Power\ Out}\\\\ \eta_{generator} = \frac{750\ KW}{800\ KW}\\\\\eta_{turbine} = 0.9375 = 93.75\%[/tex]
Now, for combined efficiency:
[tex]\eta_{combined} = \eta_{turbine}\ \eta_{generator}\\\\\eta_{combined} = (0.777)(0.937)\\\eta_{combined} = 0.728 = 72.8\%[/tex]
1) TRUE/FALSE, an example of a quantitative observation is “That is a red doll.”
2) TRUE/FALSE, Potential energy is strongest at the top of a hill.
3) F= ?, m= 18 kg, a= 2 m/s2
help me pweeeees
Answer:
1) False
2) True
3) 36N
Explanation:
1) Quantitative observation is related to number of objects . But in that example , there isn't any number.
2) Potential energy depends on height. So potential energy increases when height increases.
3) F = m×a
In the question , m = 18 kg ; a = 2m/s^2
So, F = 18×2 = 36N
Identify the type of motion that occurs when a body moves around its own center of mass.
circular
revolution
rotation
resolution
Answer:
circular
Explanation:
What two things does force depend on
Answer:
When dealing with the force of gravity between two objects, there are only two things that are important – mass, and distance or (acceleration)
Explanation:
A soccer player kicks a ball 6.5 meters. How much time is needed for the ball to travel this distance if its velocity is 22 meters per second?
. . .
. . .
. . .
!
.
Your answer is 0.30 seconds
hand pushes on table with force of 35 N forward. whats the reaction force
Answer:
i think it is newtons third law of motion but i'm not sure sorry.i just really need point i don't know the answer.
Explanation:
A child pushes his younger brother with 54 newtons of force, causing him to accelerate at 3.8 m/s/s. Assuming no friction, what is the mass of the younger brother?
Answer to one decimal.
Answer:
force normal = mass times acceleration
F=ma
54= m (3.8)
divide by 3.8 in both sides
54/3.8
mass of the little brother is 14.2 kg
What do we know about the relative strength of the electric field around each object?
Answer:
A charged object in an electric field experiences a force due to the field. The electric field strength, E, at a point in the field is defined as the force per unit charge on a positive test charge placed at that point.
Explanation:
Which of the following best describes refraction?
Answer:
The medium sound waves
Explanation:
change in the direction of a wave passing from one medium to another.
This equation shows the reaction that occurs when charcoal burns. What type
of reaction is it?
Explanation:
Exothermic
Because here Energy is released.
Answer:
c
Explanation:
In interactions of action-reaction pairs involving Earth and everyday objects, the effect on Earth's motion is often negligible because
Answer:
...The earth has a great mass. Since mass and inertia are directly proportional to each other, the larger the mass of the object, the more inertia that it has. Inertia is the objects resistance to a change in motion.
Explanation:
An asteroid orbits the Sun every 176 years. What is the asteroids average distance from the Sun? P ^ 2 = a ^ 3 where p = period in years and average orbital distance in AU 233 years 1.46 AU 5.45 years 3.09 years
Answer:
The value is [tex]x = 45.99 \ Au[/tex]
Explanation:
From the question we are told that
The period of the asteroid is [tex]T = 176 \ years = 176 * 365 * 24 * 60* 60 = 5.55*10^{9}\ s[/tex]
Generally the average distance of the asteroid from the sun is mathematically represented as
[tex]R = \sqrt[3]{ \frac{G M * T^2 }{4 \pi} }[/tex]
Here M is the mass of the sun with a value
[tex]M = 1.99*10^{30} \ kg[/tex]
G is the gravitational constant with value [tex]G = 6.67 *10^{-11} \ m^3 \cdot kg^{-1} \cdot s^{-2}[/tex]
[tex]R = \sqrt[3]{ \frac{6.67 *10^{-11} * 1.99*10^{30} * [5.55 *10^{9}]^2 }{4 * 3.142 } }[/tex]
=> [tex]R = 6.88 *10^{12} \ m[/tex]
Generally
[tex]1.496* 10^{11} \ m \to 1 Au (Astronomical \ unit )[/tex]
So
[tex]R = 6.88 *10^{12} \ m \ \ \ \ \to \ \ x \ Au[/tex]
=> [tex]x = \frac{6.88 *10^{12}}{1.496 *10^{11}}[/tex]
=> [tex]x = 45.99 \ Au[/tex]
What type of force is magnetic force? *
Strong Nuclear force
Non-contact force
Contact force. Weak Nuclear force
Answer:
non contant force
Explanation:
bcoz they push or pull on object without touching them
Answer:
energy
Explanation:
A phase diagram assumes______
is kept constant.
Odensity
O volume
O temperature
O pressure
a 50.0kg skydiver experience a 740newton air resistance force determine her acceleration please help asap
Answer:
a = - 5 [m/s²].
Explanation:
To solve this problem we must use Newton's second law, which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
∑F = m*a
where:
F = resultant force [N] (units of Newtons)
m = mass = 50 [kg]
a = acceleration = 9.81 [m/s²]
For this particular problem, the only forces acting are the force of gravity acting down with negative sign, while the force of air opposes the fall, in this way it is positive.
[tex]f_{air}-F_{grav}=-m*a[/tex]
As the movement is pointing down the acceleration will be taken as negative.
[tex]740-(50*9.81)=-50*a\\740-490.5 = -50*a\\249.5 = -50*a\\a = - 5 [m/s^{2} ][/tex]
We should note that in this case, the acceleration has a negative sign, this means that the force of the air makes the skydiver move upwards
D. Ampere
A screw of length 5 cm enters totally into a wooden block after 25 turns. What is the pitch of the
screw?
A. 0.1 cm
B. 0.2 cm
C. 0.4 cm
D. 0.5 cm
Answer:
0.5
Explanation:
u must simplyfiy
Sonya pushes his friend down the road on his new wagon. Which two terms accurately describe the net force acting on the sled?
Group of answer choices
balanced and contact
unbalanced and noncontact
balanced and noncontact force
unbalanced and contact
Answer:
unbalanced and contact
Explanation:
The two terms that bests describes the net force acting on the sled is an unbalanced and contact force.
Force is a pull or push on a body. We have two main types of forces. Contact forces acts on a body and they must be in touch with it. An example is frictional force.
Non - contact forces acts based on force field and they are not in contact with the body. An example is gravitational force.
Since the sled is sliding down the road, it is changing velocity and so, unbalanced forces are acting on it.Therefore, the force on the wagon is an unbalanced and contact force.
A fireboat is to fight fires at coastal areas by drawing seawater with a density of 1030 kg/m3 through a 10-cm-diameter pipe at a rate of 0.04 m3/s and discharging it through a hose nozzle with an exit diameter of 5 cm. The total irreversible head loss of the system is 3 m, and the position of the nozzle is 3 m above sea level. For a pump efficiency of 70 percent, determine the required shaft power input to the pump and the water discharge velocity.
Answer:
50.93 m/s
199.5 kW
Explanation:
From the question, the nozzle exit diameter = 5 cm, Radius= diameter/2= 5cm/2= 2.5cm. we can convert it to metre for unit consistency= (2.5×0.01)=
0.025m
We can calculate the The cross sectional area of the nozzle as
A= πr^2
A= π ×0.025^2
= 1.9635 ×10^- ³ m²
From the question, the water is moving through the pipe at a rate of 0.1 m /s , then for the water to move through it at a seconds, it must move at
(0.1 / 1.9635 ×10^- ³ m²)
= 50.93 m/s
During the Operation of the pump, the Dynamic energy of the water= potential energy provided there is no loss during the Operation
mgh = 1/2mv²
We can make "h" subject of the formula, which is the height of required head of water
h = (1/2mv²)/mg
h= v² / 2g
h = 50.93² / (2 ×9.81)
h = 132.21m
From the question;
The total irreversible head loss of the system = 3 m,
the given position of nozzle = 3 m
the total head the pump needed=(The total irreversible head loss of the system + the position of the nozzle + required head of water )
=(3 + 3 + 132.21m)
=138.21m
mass of water pumped in a seconds can be calculated since we know that mass is a product of volume and density
Volume= 0.1m³
Density of sea water=1030 kg/m
(0.1 m^3× 1030)
= 103kg
We can calculate the Potential enegry, which is = mgh
= (103 ×9.81 × 138.21)
= 139651.5 Watts
= 139.65kW
To determine required shaft power input to the pump and the water discharge velocity
Energy= efficiency × power
But we are given efficiency of 70 percent, then
139651.5 Watts = 0.7P
=199502.18 Watts
P=199.5 kW
Therefore, the required shaft power input to the pump and the water discharge velocity is 199.5 kW
!!!!!!!!!!!!!!!!!!PLEASE HELP QUICK 30 BRAINLY POINTS!!!!!!!!!!!!!!
A two-stage rocket accelerates from rest at +3.57 m/s/s for 6.82 seconds. It then
accelerates at +2.98 m/s/s for another 5.90 seconds. After the second stage, it enters
into a state of free fall. Determine:
a. the maximum speed
b. the maximum altitude
c. the height of the rocket after 20.0 seconds
d. the total time the rocket is in the air (assuming it is launched from the ground)
!!!!!!!!!!!!!!!!!!PLEASE HELP QUICK 30 BRAINLY POINTS!!!!!!!!!!!!!!
Answer:
i need points
Explanation:
i need points
Answer:
this is old so-
Explanation:
Which of the following is an example of light energy being changed to chemical energy?
A flashlight with rechargeable batteries
A solar panel that charges a battery
Food that is eaten to provide mechanical energy
A switch that flips up to turn on a light
Answer:
solar panels that charges battery
A rock is dropped into a canyon that is 0.3 km deep. Determine the time it takes the rock to hit the bottom of the canyon?
Answer:
rock of mass m is dropped to the ground from a height h. A second rock, with mass 2m, is dropped from the same height. When the second rock strikes the ground, what is its kinetic energy? (a) Twice that of the first rock, (b) four times that of the first rock, (c) same as that of the first rock, (d) half as much as that of the first rock, (e) impossible to determine.
If a rock is dropped into a canyon that is 0.3 km deep, then the time taken by the rock to hit the bottom of the canyon would be 7.82 seconds.
What are the three equations of motion?There are three equations of motion given by Newton
v = u + at
S = ut + 1/2 × a × t²
v² - u² = 2 × a × s
Keep in mind that these calculations only apply to uniform acceleration.
As given in the problem, if a rock is dropped into a canyon that is 0.3 km deep.
By using the second equation of motion given by Newton,
S = ut + 1/2at²
300 = 0 + 0.5 × 9.8 × t²
t² = 300 / 4.9
t = 7.82 seconds
Thus, the time taken by the rock to hit the bottom of the canyon would be 7.82 seconds.
To learn more about equations of motion here, refer to the link given below ;
brainly.com/question/5955789
#SPJ2
HELP ASAP TIMER
Three trains are all are moving along a track with the same speed and slam on their brakes. If all three trains have identical coefficients of kinetic friction with the rail surface, which train travels the longest distance to come to a stop?
a
This cannot be determined, without knowing the normal force on the train by the rail.
b
The most massive train.
c
They all travel the same distance in stopping.
d
The least massive train.
Answer:
the more massive train i think
Explanation:
more mass means kinda more energy so it will take it longer to slow since it is larger
1. Four identical elephants are at different heights. If your physics teacher
asked you which of the following elephants has the greatest amount of
potential energy, what will be your answer? And why?
Helpppp:(((((
Plz di all plz i will give brainest and thanks to best answer do it right
Answer:
B
hdhdududydysgd
hdhdgdtdtdt
gsgdgdggd
Explanation:
I TIHNK IS THE ANSWER
Answer:
C
Explanation:
Wave length is - - - - >
Bsjejwakknsbsbehebebbdbdbs
Who might be suffering from dissociative fugue?
Answer:
More common in adults.
Explanation:
Any one their to help
A popular ride at an amusment park lifts
customers up to a height of 50 m and then
drops them threw a displacement of 50 m
before slowing them to a stop. How fast
are the customers going at the 50 m
mark?
Answer:
five dollars
Explanation:
im thick lol
Please select the word from the list that best fits the definition
Wave that has vibration in a direction that is perpendicular to the motion creating it
transverse wave
longitudinal wave
mechanical wave
Answer:
Transverse wave
Explanation:
i’ll literally venmo you if you answer this with FULL EXPLANATION so i can understand please !
Answer:
The speed with which the man flies after hitting the rock is 5.5 m/s
Explanation:
The given parameters are;
The mass of the man, m₁ = 100 kg
The mass of the scooter, m₂ = 10 kg
The initial speed of the man and the scooter, v₁ = 5 m/s
The speed with which the man flies after hitting the rock = v₂
The final speed of the scooter, v₃ = 0 m/s
The momentum = Mass × Velocity and by the principle of conservation of momentum, we have;
The total initial momentum = The total final momentum
The total initial momentum = (m₁ + m₂) × v₁ = (100 + 10) × 5 = 550
The total initial momentum = 550 kg·m/s
The total final momentum = m₁ × v₂ + m₂ × v₃, which gives;
The total final momentum = 100 × v₂ + 10 × 0
By conservation of momentum, the total initial momentum = The total final momentum, we get;
550 = 100 × v₂ + 10 × 0
∴ 550 = 100 × v₂
v₂ = 550 kg·m/s/(100 kg) = 5.5 m/s
The speed with which the man flies after hitting the rock = v₂ = 5.5 m/s
6. You must turn on your headlights
A. before starting your vehicle
O B. whenever you use your windshield wipers
C. when vehicles cannot be seen at a distance of 2,000 ft.
You must turn on your headlights whenever you use your windshield wipers. The correct option is option B.
In many jurisdictions, it is a legal requirement to turn on your headlights whenever you are using your windshield wipers. This is because using windshield wipers typically indicates reduced visibility due to rain, snow, or other adverse weather conditions.
By turning on your headlights, you increase your visibility to other drivers on the road, enhancing safety.
Therefore, You must turn on your headlights whenever you use your windshield wipers. The correct option is option B.
To know more about windshield wipers:
https://brainly.com/question/28762246
#SPJ6
Why can't 41 be represented in a binary table?
Answer:
I think it is but I don't know for sure
Explanation:
41 101001
41 is 101001 on the binary table i think
why are incandescent lights fo inefficient?
Answer:
Explanation:
Incandescent bulbs are extremely inefficient because 90% of the energy is wasted as heat, with only 10% being converted to visible light. This gives incandescent bulbs a luminous efficiency rating of around 2%. Ultimately, incandescent bulbs perform better as heaters than as light sources.